Method and system for dynamically tuning and calibrating an antenna using an on-chip digitally controlled array of capacitors

ABSTRACT

Methods and systems for dynamically tuning and calibrating an antenna using on-chip digitally controlled array of capacitors are disclosed. Aspects of one method may include dynamically tuning a mobile terminal antenna (MTA) using on-chip arrays of capacitive devices. The tuning may be, for example, to compensate for center frequency drift during operation of the mobile terminal. The tuning may be accomplished by selecting capacitive devices in the on-chip arrays of capacitive devices to use in conjunction with an inductive circuit coupled to the MTA, where the inductive circuit may be either off the chip or on the chip. Accordingly, an impedance of the circuit formed by the capacitive devices in the on-chip arrays of capacitive devices and the inductive circuit may be adjusted with respect to the MTA. A valid circuit configuration may include a configuration where no capacitive device may be selected for use with the inductive circuit.

CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE

This application makes reference to:

-   U.S. application Ser. No. ______ (Attorney Docket No. 17784US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17785US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17786US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17787US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17788US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17789US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17790US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17791US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17792US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17916US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17917US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17918US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17919US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17920US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17921US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17922US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17923US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17924US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17925US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17926US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17927US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17928US01),    filed on even date herewith;-   U.S. application Ser. No. ______ (Attorney Docket No. 17929US01),    filed on even date herewith; and-   U.S. application Ser. No. ______ (Attorney Docket No. 17930US01),    filed on even date herewith.

The above stated applications are hereby incorporated herein byreference in their entirety

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[Not Applicable]

MICROFICHE/COPYRIGHT REFERENCE

[Not Applicable]

FIELD OF THE INVENTION

Certain embodiments of the invention relate to wireless communication.More specifically, certain embodiments of the invention relate to amethod and system for dynamically tuning and calibrating an antennausing an on-chip digitally controlled array of capacitors.

BACKGROUND OF THE INVENTION

Wireless devices have used antennas to receive RF signals. The size ofan antenna may depend on the wavelength of the RF signals that thewireless device is designed to receive. Typically, larger antennas areneeded for signals with larger wavelengths. Accordingly, a mobileterminal may use antennas of a few inches for signals in the GHz range.However, for FM radio signals in the 100 MHz range, the antennas mayneed to be longer. As corded headsets gained in popularity with mobileterminal users, many mobile terminal manufacturers used the headphonecord as an antenna, for example, for a FM receiver

However, with the advent of Bluetooth headsets, the need for cordedheadsets was eliminated. The mobile terminal manufacturers have devisedalternate means for implementing an FM antenna. One such antennacomprises a conductive coil or loop on a small circuit board that istypically placed at the back of the mobile terminal Since this small FMantenna is limited in size, the antenna may be tuned to support the FMradio bandwidth. Additionally, because of the circuit board antenna'slimited ability to receive FM signals, external factors may be a bigfactor to reception sensitivity. For example, a mobile terminal userholding the mobile terminal may cause the designed center frequency ofthe FM antenna to shift due to capacitive and/or inductive changes.Additionally, the mobile terminal's components, such as, the battery,may interfere with reception and/or change the antenna characteristicsof the circuit board antenna by distorting and/or shorting the circuitboard antenna.

Further limitations and disadvantages of conventional and traditionalapproaches will become apparent to one of skill in the art, throughcomparison of such systems with some aspects of the present invention asset forth in the remainder of the present application with reference tothe drawings.

BRIEF SUMMARY OF THE INVENTION

A system and/or method for dynamically tuning and calibrating an antennausing an on-chip digitally controlled array of capacitors, substantiallyas shown in and/or described in connection with at least one of thefigures, as set forth more completely in the claims.

Various advantages, aspects and novel features of the present invention,as well as details of an illustrated embodiment thereof, will be morefully understood from the following description and drawings.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a block diagram of an exemplary mobile terminal, in accordancewith an embodiment of the invention.

FIG. 2A is a block diagram illustrating an exemplary circuit that may beutilized for dynamically tuning and calibrating an antenna, inaccordance with an embodiment of the invention.

FIG. 2B is a block diagram illustrating an exemplary inductive circuitblock that may be utilized for dynamically tuning an antenna, inaccordance with an embodiment of the invention.

FIG. 2C is a block diagram illustrating an exemplary n-array capacitorblock that may be utilized for dynamically tuning an antenna, inaccordance with an embodiment of the invention.

FIG. 3 is an flow diagram of exemplary steps for dynamically tuning anantenna, in accordance with an embodiment of the invention

DETAILED DESCRIPTION OF THE INVENTION

Certain embodiments of the invention may be found in a method and systemfor dynamically tuning and calibrating an antenna using an on-chipdigitally controlled array of capacitors. Aspects of the method maycomprise dynamically tuning a mobile terminal antenna using at least oneon-chip array of capacitive devices The tuning may be utilized, forexample, to compensate for center frequency drift during operation ofthe mobile terminal The tuning may be accomplished by selectingcapacitive devices in the on-chip arrays of capacitive devices to use inconjunction with an inductive circuit coupled to the mobile terminalantenna, where the inductive circuit may be either off the chip or onthe chip. Accordingly, an impedance of the circuit formed by thecapacitive devices in the on-chip arrays of capacitive devices and theinductive circuit may be adjusted with respect to the mobile terminalantenna. A valid circuit configuration may comprise a configuration inwhich no capacitive device may be selected for use with the inductivecircuit.

The capacitive devices in the on-chip arrays of capacitive devices maybe dynamically selected in order to select a desired center frequencyfor the mobile terminal antenna. The selection of the capacitive devicesmay be based on determining a frequency offset of the center frequencyof the mobile terminal antenna from the desired center frequency. Theimpedance of a circuit comprising the capacitive devices in the on-chiparrays of capacitive devices may also be adjusted to select a specifiedbandwidth and/or to match the mobile terminal antenna to a RF front end.The impedance adjustment may be, for example, based on a measured signalstrength and/or bit error rate of signals received by the mobileterminal.

FIG, 1 is a block diagram of an exemplary mobile terminal, in accordancewith an embodiment of the invention. Referring to FIG. 1, there is showna mobile terminal 100, which may comprise, for example, an antenna 105,an antenna tuning circuit block 110, a RF front end 112, a basebandprocessor 114, a processor 116, and a system memory 118. The antennatuning circuit block 110 may comprise suitable logic, circuitry, and/orcode that may be adapted to adjust a center frequency for the antenna105. The antenna tuning circuit block 110 may also adjust a bandwidth ofsignals that may be received by the antenna 105. The antenna tuningcircuit block 110 may also adjust impedance matching between the antenna105 and the RF front end 112.

The RF front end 112 may comprise suitable logic, circuitry, and/or codethat may be adapted to process received RF signals and/or HF signals tobe transmitted. The RF front end 112 may be coupled to the antenna 105via the antenna tuning circuit 110 for signal reception and/ortransmission. With respect to received signals, the RF front end 112 maydemodulate the received signals before further processing. Moreover, theRF front end 112 may comprise other exemplary functions, such as,filtering the received signal, amplifying the received signals, and/ordownconverting the received signals to very low intermediate frequency(VLIF) signal and/or baseband signal. The RF front end 112 may comprisea IF processor which may digitize an IF signal, and digitally processthe digitized IF signal to filter and/or downconvert the digitized IFsignal to a digital baseband signal. The IF processor may then convertthe digitized baseband signal to an analog baseband signal.

The RF front end 112 may also receive digital or analog baseband signalsfrom, for example, the baseband processor 114. For example, the basebandprocessor 114 may generate one ore more signals that may be communicatedto the RF front end 112, which may be utilized to control one or morefunctions executed by the RF front 112. Accordingly, in one embodimentof the invention, one or more signals generated by the basebandprocessor 114 and/or processor 116 may be utilized to program variouscomponents such as, for example, filters, phase lock loops (PLLs) orsynthesizers, in the RF front end 112. The RF front end 112 mayappropriately filter, amplify, and/or modulate an analog signal fortransmission via the antenna 105. The RF front end 112 may also converta digital signal to an analog signal as part of processing fortransmission.

The baseband processor 114 may comprise suitable logic, circuitry,and/or code that may be adapted to process analog or digital basebandsignals generated by the RF front end 112. The baseband processor 114may also communicate baseband signals to the RF front end 112 forprocessing before transmission. The processor 116 may comprise suitablelogic, circuitry, and/or code that may be adapted to control theoperations of the antenna tuning circuit 110, the RF front end 112,and/or the baseband processor 114. For example, the processor 116 may beutilized to update and/or modify programmable parameters and/or valuesin a plurality of components, devices, and/or processing elements in theantenna tuning circuit 110, the RF front end 112, and/or the basebandprocessor 114. Exemplary programmable parameters may comprise gain of anamplifier, bandwidth of a filter, and/or PLL parameters. Control and/ordata information may be transferred from another controller and/orprocessor in the mobile terminal 100 to the processor 116. Similarly,the processor 116 may transfer control and/or data information toanother controller and/or processor in the mobile terminal 100.

The processor 116 may utilize the received control and/or datainformation to determine the mode of operation of the RF front end 112.For example, the processor 116 may select a specific frequency for alocal oscillator, or a specific gain for a variable gain amplifier.Moreover, the specific frequency selected and/or parameters needed tocalculate the specific frequency, and/or the specific gain value and/orthe parameters needed to calculate the specific gain, may be stored inthe system memory 118 via the controller/processor 116. This informationstored in system memory 118 may be transferred to the RF front end 112from the system memory 118 via the controller/processor 116. The systemmemory 118 may comprise suitable logic, circuitry, and/or code that maybe adapted to store a plurality of control and/or data information,including parameters needed to calculate frequencies and/or gain, and/orthe frequency value and/or gain value.

In operation, RF signals may be communicated to the antenna tuningcircuit 110 by the antenna 105. The antenna tuning circuit 110 maypresent an impedance to the antenna 105, and accordingly, the antenna105 in conjunction with the antenna tuning circuit 110 may have a centerfrequency and a bandwidth about the center frequency. Accordingly, theantenna 105 may present optimal reception for those signals within thebandwidth. However, various environmental conditions, including thepresence of the human body such as a user's hand holding onto the mobileterminal 100, may cause the center frequency to drift from the desiredcenter frequency. For example, the inductive or capacitivecharacteristics of the human hand may change the center frequencywhenever the hand comes in contact with the mobile terminal. The mobileterminal 100 may detect the center frequency drift and may dynamicallyconfigure the antenna tuning circuit block 110 in order to bring thecenter frequency closer to a desired center frequency. The antennatuning circuit block 110 may also be configured to adjust the bandwidthof the antenna 105 and/or the impedance matching of the antenna 105 tothe RF front end 112.

The center frequency drift may be detected, for example, by the REFfront end 112, which may receive weaker signals at the desiredfrequencies. The center frequency drift may also be detected, forexample, by processing the received signals. For example, if thereceived signals comprise digital information, the baseband processor114 may detect an increase in bit error rate, which may be indicative ofcenter frequency drift.

The signal strength indication and/or bit error rate may be communicatedto the processor 116, and the processor 116 may determine that theantenna tuning circuit block 110 may need to be reconfigured.Accordingly, the processor 116 may communicate appropriate controland/or data to the antenna tuning circuit block 110 to reconfigureand/or retune the antenna tuning circuit block 110. By processinginformation regarding the received signals, the processor 116 maydynamically adjust the center frequency in order to reduce the effectsof center frequency drift

An embodiment of the invention may have been described with the antennatuning circuit block 110 as a separate functional block, however, theinvention need not be so limited. For example, the antenna tuningcircuit block 110 may be part of the RF front end 112. Also, while theprocessor 116 may have been descried as determining when and how toconfigure the antenna tuning circuit 110, the invention need not be solimited. For example, the antenna tuning circuit block 110 may comprisefunctionality that may adjust the center frequency and/or the bandwidthof the antenna 105, and/or the impedance matching of the antenna 105 tothe RF front end 112 independently of, or in conjunction with, theprocessor 116. Additionally, while FIG. 1 may have been described ascommunicating to at least one other processor or controller, theinvention need not be so limited. Accordingly, there may be instanceswhen the processor 116 may not have to communicate with other processorsin controlling RF communications. For example, a design of the mobileterminal may not utilize other processors than the processor 116 or theprocessor 116 may have access to all information needed to control RFcommunications.

FIG. 2A is a block diagram illustrating an exemplary circuit that may beutilized for dynamically tuning an antenna, in accordance with anembodiment of the invention. Referring to FIG. 2A, there is shown acapacitive device block 202, an inductive device block 204, a connectionblock 206, and a control block 208. The capacitive device block 202 maycomprise a plurality of capacitive devices 202 a . . . 202 b. Terminalsof each capacitive device 202 a . . . 202 b may be coupled to theconnection block 206, The inductive device block 204 may comprise aplurality of inductive devices 204 a . . . 204 b. Terminals of eachinductive device 204 a . . . 204 b may be coupled to the connectionblock 206.

The connection block 206 may comprise suitable logic, circuitry, and/orcode that may enable coupling of any input terminal from the capacitivedevice block 202, the inductive device block 204, the antenna 105,and/or the connection to the RF front end to be connected to anyterminal from the capacitive device block 202, the inductive deviceblock 204, the antenna 105, and/or the connection to the RF front end112. Accordingly, the connection block 206 may configure a subset of thecapacitive devices 202 a . . . 202 b and a subset of the inductivedevices 204 a . . . 204 b to form a circuit that couples the terminalfrom the antenna 105 and the connection to the RF front end 112. Forexample, the subset may be a null subset to form a short circuit betweenthe terminal from the antenna 105 and the connection to the RF front end112. The subset of the capacitive devices 202 a . . . 202 b may also bea subset that comprises the set of capacitive devices 202 a . . . 202 b.Similarly, the subset of the inductive devices 204 a . . . 204 b may bea subset that comprises the set of inductive devices 204 a . . . 204 b.Accordingly, the subset of capacitive devices 202 a . . . 202 b mayrange from no capacitive device to all of the capacitive devices 202 a .. . 202 b in capacitive device block 202. Similarly, the subset ofinductive devices 204 a . . . 204 b may range from no inductive deviceto all of the inductive devices 204 a . . . 204 b in inductive deviceblock

The control block 208 may comprise suitable logic, circuitry, and/orcode that may enable configuration of capacitive device and/or inductivedevice circuit that may be used to receive RF signal from the antenna105. The received RF signal may be communicated to the RF front end 112.

The capacitive device and/or inductive device circuit may be configuredvia the connection block 206, where control signals from the controlblock 208 may indicate connection of the various terminals for thecapacitive devices 202 a . . . 202 b, the inductive devices 204 a . . .204 b, the antenna 105, and/or connection to the RF front end 112. Insome embodiments of the invention, the capacitive device block 202 maybe on the same chip as the inductive device block 204. In otherembodiments of the invention, the inductive device block 204 may belocated separately from the on-chip capacitive device block 202.

In operation, the control block 208 may receive data and/or commandsfrom the processor 116. The control block 208 may then send appropriatecommands to the connection block 206 in order to configure thecapacitive devices 202 a . . . 202 b and/or the inductive devices 204 a. . . 204 b to a particular circuit and connect the circuit to theterminal from the antenna 105 and to the connection to the RF front end112. For example, the control block 208 may communicate signals to theconnection block 206 such that the connection block 206 may couple thecapacitive device 202 a in parallel to the inductive device 204 a. Firstand second terminals of the resulting LC parallel circuit may be coupledto the antenna 105 and to the RF front end 112, respectively.Accordingly, the impedance of the circuit formed by the inductivedevices 204 a . . . 204 b and the capacitive devices 202 a . . . 202 bmay be changed with different circuit configurations. A change in theimpedance of the circuit formed by the inductive devices 204 a . . . 204b and the capacitive devices 202 a . . . 202 b may result in a shift inthe center frequency of the antenna 105, a change in the bandwidth ofthe antenna 105, and/or change in the impedance matching of the antenna105 to the RF front end 112.

FIG. 2B is a block diagram illustrating an exemplary inductive circuitblock that may be utilized for dynamically tuning an antenna, inaccordance with an embodiment of the invention. Referring to FIG. 2B, inan embodiment of the invention, the antenna tuning circuit block 110 maycomprise a tuning control block 210 and an inductive circuit block 230.The tuning control block 210 may comprise a control block 212 and aplurality of capacitor arrays 214, 216, . . . 218. The control block 212may comprise suitable logic, circuitry, and/or code that may enablecontrol of capacitance that may be associated with each of the capacitorarrays 214, 216, . . . 218. In some embodiments of the invention, thecapacitor arrays 214, 216, . . . 218 may be on the same chip as theinductive circuit block 220. In other embodiments of the invention, theinductive circuit block 220 may be located separately from the on-chipcapacitor arrays 214, 216, . . . 218.

The capacitor arrays 214, 216, . . . 218 may each comprise a pluralityof capacitive elements whose capacitances may be added to effectivelyform different capacitors with different capacitances. The capacitorarray 214, 216, or 218 is described in more detail with respect to FIG.2C. The inductive circuit block 220 may comprise a plurality ofinductive elements that may be coupled to the capacitor arrays 214, 216,. . . 218.

The inductive circuit block 230 illustrates an exemplary configurationfor the inductive elements of the inductive circuit block 220. Theinductive circuit block 230 may comprise a plurality of inductiveelements 230 a, 230 b, . . . 230 c in series. Each of the capacitorarrays 214, 216, . . . 218 may be coupled to a node in the inductivecircuit block 230. For example, the capacitor array 214 may be coupledto the node between the inductors 220 a and 220 b, the capacitor array216 may be coupled to the node between the inductors 220 b and 220 c,and the capacitor array 218 may be coupled to the node of the inductor220 c that is not coupled to the inductor 220 b.

In operation, the tuning control block 210 may configure the capacitivearrays 214, 216, . . . 218 for use with the inductive circuit block 230.The control block 212 may select a capacitance for each of thecapacitive arrays 214, 216, . . . , 218 by enabling individualcapacitive elements to be used for receiving RF signals from the antenna105. Accordingly, the impedance of the circuit may be varied, andthereby cause the center frequency and/or the bandwidth associated withthe antenna 105, and/or impedance matching between the antenna 105 andthe RF front end 112 may be adjusted.

While the inductive devices 230 a, 230 b, . . . , 230 c in the inductivecircuit block 230 may have been described as being in series, theinvention need not be so limited. The inductive devices 230 a, 230 b, .. . , 230 c may be placed in other configurations, such as, for example,parallel, a pi, or star configuration, as well as any combination ofserial, parallel, pi, or star configurations.

FIG. 2C is a block diagram illustrating an exemplary n-array capacitorblock that may be utilized for dynamically tuning an antenna, inaccordance with an embodiment of the invention. Referring to FIG, 2C,there is shown the capacitive array 250, which may be similar to thecapacitive arrays 214, 216, . . . , 218. The capacitive array 250 maycomprise the capacitive elements 250 a, 250 b, 250 c, . . . 250 d, theswitches 251 a, 251 b, . . . , 251 c, and the output nodes 255 and 256.

The control block 212 may control whether each of the switches 251 a,251 b, . . . , 251 c may be open or closed via the control signals tothe capacitive array 250. In instances where a switch may be open, thecorresponding capacitive element 250 b, 250 c, . . . , 250 d,respectively, may not be part of a circuit that receives the RF signalsfrom the antenna 105. Conversely, in instances where a switch may beclosed, the corresponding capacitive element may be part of the circuitthat receives the RF signals. Accordingly, the impedance of the circuitthat receives the RF signals may be adjusted by opening or closing theswitches 251 a, 251 b, . . . , 251 c. Adjusting the impedance in thismanner may adjust the center frequency and/or the bandwidth of theantenna 105, and/or the impedance matching of the antenna 105 to the RFfront end 112.

The control block 212 may receive one or more signals, for example, fromthe processor 116, which may indicate a status of the center frequencydrift for the antenna 105. The receive signal from the processor 116 maycomprise, for example, detailed information regarding switch positionsfor each capacitive array 214, 216, . . . , 218. Accordingly, thecontrol block 212 may only need nominal processing to open or close thevarious switches 251 a, 251 b, . . . , 251 c in the capacitive arrays214, 216, . . . , 218. Other embodiments of the invention maycommunicate signal integrity indicators, for example, received signalstrength indication and/or bit error rate, to the control block 212. Thecontrol block 212 may then process the signal integrity indicators todetermine the center frequency drift, and proper adjustments that may beneeded to compensate for the drift. The control block 212 may then openor close the various switches 251 a, 251 b, . . . , 251 c in thecapacitive arrays 214, 216, . . . , 218 to adjust the center frequencyand/or the bandwidth of the antenna 105, and/or the impedance matchingof the antenna 105 to the RF front end 112. Still other embodiments ofthe invention may allocate processing between the processor 116 and thecontrol block 212. For example, the processor 116 may determine theamount of drift or shift in the center frequency, while the controlblock 212 may determine a specific configuration for the capacitivearrays 214, 216, . . . , 218 based on the amount of frequencycompensation needed.

While the capacitive devices 250 a, 250 b, . . . , 250 d in thecapacitive array 250 may have been described as being in parallel, theinvention need not be so limited. The capacitive devices 250 a, 250 b, .. . , 250 d may be placed in other configurations, such as, for example,in parallel, in a pi, or star configuration, as well as any combinationof serial, parallel, pi, or star configuration. Additionally, while thecapacitive element 250 a may be shown always connected, otherembodiments of the invention may allow the capacitive element 250 a tobe switched. Accordingly, the capacitive array 250 may be configured sothat it may not be part of the circuit receiving the RF signals from theantenna 105. Notwithstanding its configuration, the capacitive array 250may have the capability to dynamically switch the amount of capacitancethat may be required to tune the center frequency to a desired value.

Additionally, FIG. 2B may indicate that the capacitive arrays 214, 216,. . . , 218 may be coupled to fixed nodes of the inductive circuit block230. However, the invention need not be so limited. For example, theterminals 255 and 256 of the capacitive array 250 may be programmablycoupled to different locations. Accordingly, in one exemplaryconfiguration, the capacitive array 214 may couple the terminal 255 toground and the terminal 256 to the node between the inductive devices220 a and 220 b. In another exemplary configuration, the capacitivearray 214 may couple the terminal 255 to the node connected only to theinductive device 220 a and the terminal 256 to the node between theinductive devices 220 a and 220 b.

FIG, 3 is an flow diagram of exemplary steps for dynamically tuning anantenna, in accordance with an embodiment of the invention. Referring toFIG. 3, there is shown exemplary steps 300 to 308. In step 300, theantenna tuning circuit block 110 may be at a nominal configuration wherethe center frequency for the antenna 105 may be at the desiredfrequency. In step 302, the mobile terminal 100 may receive desired RFsignals via the antenna 105. The mobile terminal 100 may determinewhether the center frequency may have drifted by, for example,processing the present received signal strength level compared toprevious signal strength levels. If the signal strength is decreasing,one reason may be because the center frequency may have drifted. Fordigital broadcasts, the mobile terminal 100 may also determine whether atrend for bit error rates is increasing or decreasing. If the bit errorrate is increasing, one reason may be because the center frequency mayhave drifted.

Accordingly, the mobile terminal 100 may determine whether to adjust thecenter frequency. If so, the next step may be step 302, where the mobileterminal 100 may operate without adjusting the center frequency and/orthe bandwidth of the antenna 105, and/or the impedance matching betweenthe antenna 105 and the RF front end 112. If the center frequency is tobe adjusted, the next step may be step 306 In step 306, the processor116 and the control block 212 may determine how to configure thecapacitive arrays 214, 216, . . . , 218 to move the center frequencytoward the desired nominal center frequency of step 300. In step 308,the various switches 251 a, 251 b, . . . , 251 c in the capacitivearrays 214, 216, . . . , 218 may be opened or closed to configure theantenna tuning circuit 110 to adjust the center frequency and/or thebandwidth of the antenna 105, and/or the impedance matching between theantenna 105 and the RF front end 112 appropriately. The next step may bestep 302.

In accordance with an embodiment of the invention, aspects of anexemplary system may comprise an antenna tuning circuit block 110 thatenables dynamically tuning of the antenna 105. The antenna tuningcircuit block 110 may comprise the capacitive arrays 214, 216, . . . ,218 of capacitive devices to compensate for center frequency driftduring operation of the mobile terminal. The impedance due thecapacitive arrays 214, 216, . . . 218 and the inductive circuit block220 coupled to the antenna 105 may be adjusted to adjust the centerfrequency and/or bandwidth of the antenna 105, and/or the impedancematching between the antenna 105 and the RF front end 112. The tuningcontrol block 210 may adjust the impedance by dynamically selectingcapacitive devices in the capacitive arrays 214, 216, . . . , 218 tooperate to receive the RF signals from the antenna 105 The capacitivearrays 214, 216, . . . , 218 may be on a chip, while the inductivecircuit block 220 may be on the same chip or not.

The selection of the capacitive devices in the capacitive arrays 214,216, . . . , 218 may be based on a determination of a frequency offsetfrom the desired center frequency. The frequency offset may bedetermined by, for example, the processor 116. If the center frequencyneeds to be adjusted, the processor 116 may indicate to the tuningcontrol block 210 the appropriate capacitive elements to be used in thecapacitive arrays 214, 216, . . . , 218. The tuning control block 210may also adjust the impedance due the capacitive arrays 214, 216, . . .218 and the inductive circuit block 220 coupled to the antenna 105 byappropriately configuring the capacitive arrays 214, 216, . . . , 218 toselect a specified bandwidth. The tuning control block 210 may alsoadjust the impedance due the capacitive arrays 214, 216, . . . 218 andthe inductive circuit block 220 to impedance match the antenna 105 tothe RE front end 112. The tuning control block 210 may adjust theimpedance based on a measured signal strength and/or the bit error rateof signals received via the antenna 105.

Another embodiment of the invention may provide a machine-readablestorage, having stored thereon, a computer program having at least onecode section executable by a machine, thereby causing the machine toperform the steps as described above for dynamically tuning andcalibrating an antenna using on-chip digitally controlled array ofcapacitors. In various exemplary embodiments of the invention, any oneor more of: the antenna tuning circuit 100, the RF front end 112, thebaseband processor 114, and the processor 116, may be controlled bysoftware and/or firmware.

Accordingly, the present invention may be realized in hardware,software, or a combination of hardware and software. The presentinvention may be realized in a centralized fashion in at least onecomputer system, or in a distributed fashion where different elementsare spread across several interconnected computer systems. Any kind ofcomputer system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may be a general-purpose computer system with a computerprogram that, when being loaded and executed, controls the computersystem such that it carries out the methods described herein.

The present invention may also be embedded in a computer programproduct, which comprises all the features enabling the implementation ofthe methods described herein, and which when loaded in a computer systemis able to carry out these methods. Computer program in the presentcontext means any expression, in any language, code or notation, of aset of instructions intended to cause a system having an informationprocessing capability to perform a particular function either directlyor after either or both of the following. a) conversion to anotherlanguage, code or notation; b) reproduction in a different materialform.

While the present invention has been described with reference to certainembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the scope of the present invention. In addition, manymodifications may be made to adapt a particular situation or material tothe teachings of the present invention without departing from its scope.Therefore, it is intended that the present invention not be limited tothe particular embodiment disclosed, but that the present invention willcomprise all embodiments falling within the scope of the appendedclaims.

1. A method for wireless communication, the method comprising:dynamically tuning a mobile terminal antenna using at least one on-chiparray of capacitive devices to compensate for center frequency driftduring operation of said mobile terminal, wherein said at least oneon-chip array of capacitive devices and an inductive circuit coupled tosaid mobile terminal antenna are used to adjust impedance of said mobileterminal antenna.
 2. The method according to claim 1, wherein saidinductive circuit is off said chip.
 3. The method according to claim 1,wherein said inductive circuit is on said chip.
 4. The method accordingto claim 1, comprising dynamically selecting capacitive devices in saidat least one on-chip array of capacitive devices to select a desiredcenter frequency for said mobile terminal antenna.
 5. The methodaccording to claim 4, comprising determining a frequency offset fromsaid desired center frequency.
 6. The method according to claim 5,comprising adjusting said at least one on-chip array of capacitivedevices based on said determining.
 7. The method according to claim 1,comprising adjusting said impedance to select a specified bandwidth. 8.The method according to claim 1, comprising adjusting said impedancebased on a measured signal strength of signals received via said mobileterminal antenna.
 9. The method according to claim 1, comprisingadjusting said impedance based on a bit error rate of signals receivedvia said mobile terminal antenna.
 10. A method for wirelesscommunication, the method comprising: dynamically tuning a mobileterminal antenna by configuring a first subset of capacitive deviceswith a second subset of inductive devices to compensate for centerfrequency drift during operation of said mobile terminal and to controlbandwidth of said mobile terminal antenna, wherein said at least oneon-chip array of capacitive devices and an inductive circuit coupled tosaid mobile terminal antenna are used to adjust impedance of said mobileterminal antenna.
 11. A machine-readable storage having stored thereon,a computer program having at least one code section for wirelesscommunication, the at least one code section being executable by amachine for causing the machine to perform steps comprising: dynamicallytuning a mobile terminal antenna using at least one on-chip array ofcapacitive devices to compensate for center frequency drift duringoperation of said mobile terminal, wherein said at least one on-chiparray of capacitive devices and an inductive circuit coupled to saidmobile terminal antenna are used to adjust impedance of said mobileterminal antenna.
 12. The machine-readable storage according to claim11, wherein said inductive circuit is off said chip.
 13. Themachine-readable storage according to claim 11, wherein said inductivecircuit is on said chip.
 14. The machine-readable storage according toclaim 11, wherein said at least one code section comprises code fordynamically selecting capacitive devices in said at least one on-chiparray of capacitive devices to select a desired center frequency forsaid mobile terminal antenna.
 15. The machine-readable storage accordingto claim 14, wherein said at least one code section comprises code fordetermining a frequency offset of center frequency of said mobileterminal antenna from said desired center frequency.
 16. Themachine-readable storage according to claim 15, wherein said at leastone code section comprises code for adjusting said at least one on-chiparray of capacitive devices based on said determining.
 17. A Themachine-readable storage according to claim 11, wherein said at leastone code section comprises code for adjusting said impedance to select aspecified bandwidth.
 18. The machine-readable storage according to claim11, wherein said at least one code section comprises code for adjustingsaid impedance based on a measured signal strength of signals receivedvia said mobile terminal antenna.
 19. The machine-readable storageaccording to claim 11, wherein said at least one code section comprisescode for adjusting said impedance based on a bit error rate of signalsreceived via said mobile terminal antenna.
 20. A system for wirelesscommunication, the system comprising: control circuitry that enablesdynamically tuning of a mobile terminal antenna using at least oneon-chip array of capacitive devices to compensate for center frequencydrift during operation of said mobile terminal, wherein said at leastone on-chip array of capacitive devices and an inductive circuit coupledto said mobile terminal antenna are used to adjust impedance of saidmobile terminal antenna.
 21. The system according to claim 20, whereinsaid inductive circuit is off said chip.
 22. The system according toclaim 20, wherein said inductive circuit is on said chip.
 23. The systemaccording to claim 20, wherein said control circuitry dynamicallyselects capacitive devices in said at least one on-chip array ofcapacitive devices to select a desired center frequency for said mobileterminal antenna.
 24. The system according to claim 23, comprisingprocessing circuitry that enables determination of a frequency offsetfrom said desired center frequency.
 25. The system according to claim24, wherein said control circuitry adjusts said at least one on-chiparray of capacitive devices based on said determining by said processingcircuitry.
 26. The system according to claim 20, wherein said controlcircuitry adjusts said impedance to select a specified bandwidth. 27.The system according to claim 20, wherein said control circuitry adjustssaid impedance based on a measured signal strength of signals receivedvia said mobile terminal antenna.
 28. A The system according to claim20, wherein said control circuitry adjusts said impedance based on a biterror rate of signals received via said mobile terminal antenna.
 29. Asystem for communicating information in a wireless communication system,the system comprising: at least one circuit that dynamically controls afrequency of received RF signal to compensate for center frequencydrift, and said at least one circuit enables dynamic configuration of atleast one antenna that receives said RE signal.